1. Field of the Invention
The present invention relates to a wick assembly and, more particularly, to a wick assembly made of metal and provided for being mounted to a lamp device for precisely controlling the flame combustion scale.
2. Description of the Related Art
A conventional lamp device includes a fuel cup storing fuel, and a wick connecting into fuel stored in the fuel cup. Moreover, the wick is normally made out of braided cotton and works by capillary action. Fuel is drawn up through the wick to reach the flame produced on the disk. The above lamp device is actively used for various purposes, such as lighting, decorating, or increasing atmosphere. For example, an oil lamp is used in religion, or an alcohol lamp is used in medical or chemical laboratories.
The conventional cotton wick must be cut to a predetermined length adapted for being mounted to the lamp device. However, after trimming, the cotton wick is easily loosened at its terminal end. After ignition, fuel vaporizes and combusts on the wick, and the tip of the cotton wick will be carbonized and burnt out gradually on the tip due to the higher temperature on the top of flame. Thus, the cotton wick must be pulled out and trimmed to a certain length every once in a while to maintain combustion scale. Trimming the cotton wick results in the wick eventually being unconnected with fuel, so that users can only replenish fuel or replace a new wick. It is inconvenient and wasteful.
The wick length, diameter, stiffness and fire-resistance are major factors used to adjust fuel wicking and flame scale for the lamp device. However, cotton wicks with low stiffness and low fire-resistance cannot be adjusted easily to maintain proper fuel wicking and flame scale, especially for high viscosity or high flash point fuels, resulting in producing carbon deposits and difficulty to ignite. If the fuel drawn is slower than it burns, the wick will be carbonized and burnt out. If the fuel drawn is more than it burns, usually occurring on burning high flash point fuel, it will cause slow evaporation of the fuel and will produce soot due to incomplete combustion. Incomplete combustion not only produces soot but also toxic fumes.
Taiwan Patent No. 493,722 discloses a wick including a plurality of fiberglass filaments disposed and assembled at a center thereof to form a fiberglass layer, and a plurality of fiberglass yarns and melted silks arranged around the fiberglass layer. The fiberglass layer is able to draw fuel by capillary action, is hard to burn down, and is not easily loosened at its terminal end. However, the fiberglass layer does not draw fuel effectively to cause the flame to be extinguished easily and cause the flame scale difficult to be controlled. Moreover, Taiwan Patent No. 580,106 discloses a wick including a cotton thread to draw fuel and a plurality of fiberglass filaments covering around the cotton thread to avoid the cotton thread diverging, to provide a compound wick.
Therefore, the wick disclosed by said patents both include fiberglass filaments, but fiberglass is expensive with difficult processing. Momentously, the wick is a large quantity of consumable items, but the fiberglass wick is expensive and not environment-friendly. Additionally, when the fiberglass wick is processed, inhaling the fiberglass can cause damage to human lungs and be harmful to manufacturing personnel Inhaling of fiberglass will jeopardize the health of workers during fiberglass-reinforced plastic processing. The fiberglass fiber can also cause skin, eye and throat irritation to users. At higher exposure levels, fiberglass also has been associated with skin rashes and difficulty in breathing.
Likewise, the fiberglass wick will be carbonized and burned out during combustion, but only slower than a cotton wick, so that the fiberglass wick needs to be trimmed also. Furthermore, the fiberglass wick and the cotton wick sag easily due to gravity when they are saturated with fuel. Thus, the user cannot adjust the flame height or scale easily. If a user wants to adjust the flame height or scale, the user has to pull the wick out from the lamp device constantly. At the same time, the user may also contact fuel in the wick and cause inconvenience or even danger.
The present invention is, therefore, intended to obviate or at least alleviate the problems encountered in the prior art.